Long-term effectiveness of family-based pediatric obesity treatment (FBT) is limited. The obesogenic environment threatens the family's ability to maintain healthy weight management behaviors, yet most interventions focus only on the parent-child dyad (changes in parenting) ignoring the larger social-relational context. Existing interventions teach parents and children behavioral skills needed for weight management and short-term adherence, but a failure of the proximal social environment to support maintenance of behavior change severely challenges their long-term success. Our preliminary data suggest that naturally-occurring social networks can and should be engaged in support of parents'attempts to manage their children's weight status. This R21 exploratory pilot address the role of parents'social network on the behavior change process. Its aims are (1) to develop an innovative intervention that capitalizes on naturally-occurring relationships to engage the parents'social support networks to enhance maintenance of healthy behaviors and better weight management (Social Network Engagement intervention, or SNE);and (2) to pilot this intervention in a single- arm trial. Novel elements of this intervention include the use of sociometric data to create a SNE strategy as well as teaching parents core skills to promote supportive interaction with their family and friends. The pilot trial will (a) assess the acceptability and feasibility of intervention, (b) evaluate its impact on intervention targets (problem-solving skill, social support and social network characteristics) and (c) estimate effect size with respect to child BMI. Our multi-disciplinary research team has expertise in pediatric obesity treatment, behavior change, and social networks. This study is among the first to assess and enhance social support networks surrounding the family as a means of changing the social environment to promote maintenance of obesity reduction behaviors. PUBLIC HEALTH RELEVANCE: This exploratory pilot project addresses the failure of pediatric obesity treatment to lead to sustained health behavior change and capitalizes on parents'naturally occurring social networks to create a more supportive social environment for weight management. We will develop a Social Network Engagement (SNE) Intervention that will be integrated into a standard treatment program for childhood overweight. We will conduct a pilot trial of SNE to assess its feasibility and take steps toward and full-scale evaluation.